Leads implanted in or about the heart have been used to reverse certain life threatening arrhythmia, or to stimulate contraction of the heart. Electrical energy is applied to the heart via electrodes on the leads to return the heart to normal rhythm.
A header on an implantable device is used to couple a conductor of a lead with the implantable device. For instance, a connector assembly in the header is used to couple a cardiac stimulator system such as a pacemaker, an anti-tachycardia device, a cardiac heart failure device, a cardioverter or a defibrillator with a lead having an electrode for making contact with a portion of the heart. The lead is typically coupled to the header using a set-screw to stabilize the lead.